1. Field of the Invention
The present invention relates to a clock movement with a display for world time zones, and particularly to a clock movement, with which an hour hand can provide a relative displacement by way of turning a time zone adjustable ring such that the dial plate thereof can show the time of a specific zone in the world directly.
2. Description of Related Art
It is known that the international exchange is getting more frequent and the transnational contact is getting popular due to the advance of the traffic and communication. In order to consider the factor with regard to the transmission of information and to the time difference, a clock possible to show the time of any other zone, or the so-called world time clock is developed to respond the necessity.
Mostly, a conventional world time clock at the dial thereof is printed with a world map and a local time is looked up in the world map. The deficiency involved in the conventional world time clock is that the dial appears too much complicated and it does not fulfill the criterion of human engineering from the standpoint of vision cognition and transmission.
Taking the U.S. Pat. No. 4,972,392 as an example, the world clock disclosed provides a 12-hour movement with a belt externally connecting with a time zone map to correspond to an hour ring with 24 equal hour divisions. The shortcoming of this world clock is that the belt drive may cause a frictional wear to influence the accuracy of time. In addition, the minute hand of the world time clock is hard to be read by means of the accustomed way.
Next, taking a simple type of world time clock as another example, the movement of this world time clock provides a 24-hour display and the periphery of the dial thereof engages with a time zone ring with 24 typical city names thereon to represent 24 time zones. When the local city name is turned to correspond to the local time in the time zone ring, the time of another related city can be figured out. However, the simple type of world time clock is also involved in a defect that the movement has to provide a 24-hour display. Moreover, the time zone ring is easily loosened after using a period of time caused by no locating device available for the time zone ring being steadily attached to the dial such that it may result in a difficulty of reading the time. Besides, the time zone ring on the simple type of world time clock is disposed to have a distance from the 24-hour graduation on the dial so that it is easy to occur a reading error. Furthermore, the dial has to be arranged with 24 graduations standing for 24 hours and the gap between two neighboring hour graduations is reduced in a limited space such that it is unfavorable for the reading of minute hand and it is not possible for the alarm being aligned accurately. This is the reason why the ordinary world time clock usually does not provide the alarm time.
An object of the present invention is to provide a clock movement with a display for world time zones, which has a 12-hour movement associated with a time zone adjustable ring to show the time in the respective time zone conveniently and accurately.